Intermittent hypoxia increases lipid insulin resistance in healthy humans: A randomized crossover trial.

Sympathetic overactivity caused by chronic intermittent hypoxia is a hallmark of obstructive sleep apnea. A high sympathetic tone elicits increases in plasma free fatty acid and insulin. Our objective was to assess the impact of 14 nights of chronic intermittent hypoxia exposure on sympathetic activity, glucose control, lipid profile and subcutaneous fat tissue remodelling in non-obese healthy humans. In this prospective, double-blinded crossover study, 12 healthy subjects were randomized, among them only nine underwent the two phases of exposures of 14 nights chronic intermittent hypoxia versus air. Sympathetic activity was measured by peroneal microneurography (muscle sympathetic nerve activity) before and after each exposure. Fasting glucose, insulin, C-peptide and free fatty acid were assessed at rest and during a multisampling oral glucose tolerance test. We assessed histological remodelling, adrenergic receptors, lipolysis and lipogenesis genes expression and functional changes of the adipose tissue. Two weeks of exposure of chronic intermittent hypoxia versus ambient air significantly increased sympathetic activity (p = 0.04). Muscle sympathetic nerve activity increased from 24.5 [18.9; 26.8] before to 21.7 [13.8; 25.7] after ambient air exposure, and from 20.6 [17.4; 23.9] before to 28.0 [24.4; 31.5] bursts per min after exposure to chronic intermittent hypoxia. After chronic intermittent hypoxia, post-oral glucose tolerance test circulating free fatty acid area under the curve increased (p = 0.05) and free fatty acid sensitivity to insulin decreased (p = 0.028). In adipocyte tissue, intermittent hypoxia increased expression of lipolysis genes (adipocyte triglyceride lipase and hormone-sensitive lipase) and lipogenesis genes (fatty acid synthase; p < 0.05). In this unique experimental setting in healthy humans, chronic intermittent hypoxia induced high sympathetic tone, lipolysis and decreased free fatty acid sensitivity to insulin. This might participate in the trajectory to systemic insulin resistance and diabetes for patients with obstructive sleep apnea.

Long-Term Efficacy and Safety of Pitolisant for Residual Sleepiness Due to OSA.

BACKGROUND: In people with OSA, excessive daytime sleepiness is a prominent symptom and can persist despite adherence to CPAP, the first-line therapy for OSA. Pitolisant was effective in reducing daytime sleepiness in two 12-week randomized controlled trials (RCTs), one in patients adherent to CPAP (BF2.649 in Patients With OSA and Treated by CPAP But Still Complaining of EDS [HAROSA 1]) and the other in patients refusing or not tolerating CPAP (BF2.649 in Patients With OSA, Still Complaining of EDS and Refusing to be Treated by CPAP [HAROSA 2]). RESEARCH QUESTION: Does the efficacy and safety of pitolisant persist when these patients take it long-term? STUDY DESIGN AND METHODS: All adults included in the HAROSA 1 and HAROSA 2 RCTs (both pitolisant and placebo arms) were offered pitolisant (up to 20 mg/d) after completion of the short-term double-anonymized phase (ie, from week 13) in an open-label cohort study. The primary efficacy outcome was the change in Epworth Sleepiness Scale score between baseline and week 52. Safety outcomes were treatment-emergent adverse event(s) (TEAE[s]), serious TEAEs, and special interest TEAEs. RESULTS: Out of 512 adults included in the two RCTs, 376 completed the 1-year follow-up. The pooled mean difference in Epworth Sleepiness Scale score from baseline to 1 year for the intention-to-treat sample was -8.0 (95% CI, -8.3 to -7.5). The overall proportions of TEAEs, serious TEAEs, and TEAEs of special interest were 35.1%, 2.0%, and 11.1%, respectively, without any significant difference between patients in the initial pitolisant and placebo arms. No cardiovascular safety issues were reported. INTERPRETATION: Pitolisant is effective in reducing daytime sleepiness over 1 year in adults with OSA, with or without CPAP treatment. Taken for 1 year, it has a good safety profile (including cardiovascular). TRIAL REGISTRATION: ClinicalTrials.gov; Nos.: NCT01071876 and NCT01072968; URL: www. CLINICALTRIALS: gov.

The carbon footprint of ambulatory gastrointestinal endoscopy.

BACKGROUND: Endoscopy is considered the third highest generator of waste within healthcare. This is of public importance as approximately 18 million endoscopy procedures are performed yearly in the USA and 2 million in France. However, a precise measure of the carbon footprint of gastrointestinal endoscopy (GIE) is lacking. METHODS: This retrospective study for 2021 was conducted in an ambulatory GIE center in France where 8524 procedures were performed on 6070 patients. The annual carbon footprint of GIE was calculated using "Bilan Carbone" of the French Environment and Energy Management Agency. This multi-criteria method accounts for direct and indirect greenhouse gas (GHG) emissions from energy consumption (gas and electricity), medical gases, medical and non-medical equipment, consumables, freight, travel, and waste. RESULTS: GHG emissions in 2021 were estimated to be 241.4 tonnes CO2 equivalent (CO2e) at the center, giving a carbon footprint for one GIE procedure of 28.4 kg CO2e. The main GHG emission, 45 % of total emissions, was from travel by patients and center staff to and from the center. Other emission sources, in rank order, were medical and non-medical equipment (32 %), energy consumption (12 %), consumables (7 %), waste (3 %), freight (0.4 %), and medical gases (0.005 %). CONCLUSIONS: This is the first multi-criteria analysis assessing the carbon footprint of GIE. It highlights that travel, medical equipment, and energy are major sources of impact, with waste being a minor contributor. This study provides an opportunity to raise awareness among gastroenterologists of the carbon footprint of GIE procedures.

Effect of adaptive servo-ventilation for central sleep apnoea in systolic heart failure on muscle sympathetic nerve activity: a SERVE-HF randomised ancillary study.

BACKGROUND: Adaptive servo-ventilation (ASV) effectively suppresses central sleep apnoea (CSA) but has been associated with increased all-cause and cardiovascular mortality in chronic heart failure patients with reduced ventricular ejection fraction (HFrEF). All-cause and, especially, cardiovascular mortality in chronic heart failure is highly correlated with sympathetic tone. This analysis of SERVE-HF data investigated the effect of ASV on sympathetic tone in patients with HFrEF and CSA. METHODS: HFrEF patients in the SERVE-HF trial (left ventricular ejection fraction (LVEF) ≤45%, apnoea-hypopnoea index (AHI) ≥15 events·h-1 with predominant CSA) were randomly assigned to receive guideline-based heart failure treatment alone (controls) or plus ASV. For this analysis, the primary outcome was change in muscle sympathetic nerve activity (MSNA) at 3-month follow-up. The effects of baseline MSNA and change in MSNA over time on mortality in the main study were also assessed. RESULTS: 40 patients with HFrEF were included in this analysis (age 71.3±11.7 years, LVEF 34.2±7.7%, 57.5% in New York Heart Association (NYHA) Functional Class II, 42.5% in NYHA Functional Class III, AHI 35.2±11 events·h-1). Sympathetic tone evolution during follow-up did not differ between groups (controls: 47.6±8.3 bursts·min-1 at baseline to 44.6±11.2 bursts·min-1; ASV group: 43.0±9.0 bursts·min-1 at baseline to 42.74±9.45 bursts·min-1). The reduction in sympathetic tone was associated with significantly increased cardiovascular mortality in the ASV group, whereas in the control group reduced sympathetic tone appeared to be protective. CONCLUSIONS: Suppression of CSA with ASV did not seem to have a significant effect on chronic heart failure-related sympathetic activation. Simultaneous suppression of CSA and reduction in MSNA was associated with increased cardiovascular mortality.

Effect of adaptive servo ventilation on central sleep apnea and sleep structure in systolic heart failure patients: polysomnography data from the SERVE-HF major sub study.

This SERVE-HF (Treatment of Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients With Heart Failure) sub study analysis evaluated polysomnography (PSG) data in patients with heart failure with reduced ejection fraction (HFrEF) and predominant central sleep apnea (CSA) randomised to guideline-based medical therapy, with or without adaptive servo ventilation (ASV). Patients underwent full overnight PSG at baseline and at 12 months. All PSG recordings were analysed by a core laboratory. Only data for patients with baseline and 3- or 12-month values were included. The sub study included 312 patients; the number with available PSG data differed for each variable (94-103 in the control group, 77-99 in the ASV group). After 12 months, baseline-adjusted respiratory measures were significantly better in the ASV group versus control. Although some between-group differences in sleep measures were seen at 12 months (e.g., better sleep efficiency in the ASV group), these were unlikely to be clinically significant. The number of periodic leg movements during sleep (PLMS) increased in the ASV group (p = 0.039). At 12 months, the respiratory arousal index was significantly lower in the ASV versus control group (p < 0.001), whilst the PLMS-related arousal index was significantly higher in the ASV group (p = 0.04 versus control). ASV attenuated the respiratory variables characterising sleep apnea in patients with HFrEF and predominant CSA in SERVE-HF. Sleep quality improvements during ASV therapy were small and unlikely to be clinically significant. The increase in PLMS and PLMS-related arousals during ASV warrants further investigation, particularly relating to their potential association with increased cardiovascular risk.

Sleep apnoea and heart failure.

Heart failure and sleep disordered breathing (SDB) are two common conditions that frequently overlap and have been studied extensively in the past three decades. Obstructive sleep apnoea (OSA) may result in myocardial damage due to intermittent hypoxia that leads to increased sympathetic activity and transmural pressures, low-grade vascular inflammation, and oxidative stress. On the other hand, central sleep apnoea and Cheyne-Stokes respiration (CSA-CSR) occurs in heart failure, irrespective of ejection fraction, either reduced (HFrEF), preserved (HFpEF) or mildly reduced (HFmrEF). The pathophysiology of CSA-CSR relies on several mechanisms leading to hyperventilation, breathing cessation and periodic breathing. Pharyngeal collapse may result at least in part from fluid accumulation in the neck, owing to daytime fluid retention and overnight rostral fluid shift from the legs. Although both OSA and CSA-CSR occur in heart failure, the symptoms are less suggestive than in typical (non-heart failure-related) OSA. Overnight monitoring is mandatory for a proper diagnosis, with accurate measurement and scoring of central and obstructive events, since the management will be different depending on whether the sleep apnoea in heart failure is predominantly OSA or CSA-CSR. SDB in heart failure is associated with worse prognosis, including higher mortality, than in patients with heart failure but without SDB. However, there is currently no evidence that treating SDB improves clinically important outcomes in patients with heart failure, such as cardiovascular morbidity and mortality.

Detecting COVID-19 and other respiratory infections in obstructive sleep apnoea patients through CPAP device telemonitoring.

OBJECTIVE: The earliest possible detection of individuals with COVID-19 has been essential to curb the spread of infection. Existing digital tools have been scaled up to address this issue. Every night telemonitoring data on continuous positive airway pressure (CPAP) device use, the first-line therapy for obstructive sleep apnoea (OSA), is collected worldwide. We asked whether the changes in CPAP adherence patterns of might constitute an alert for COVID-19. METHODS: We analysed preliminary results of telemonitoring data, recorded between February 1 and April 30, 2020, on OSA patients followed by our sleep clinics and diagnosed with COVID-19. RESULTS: CPAP telemonitoring data from the first 19 patients diagnosed with COVID-19 showed a clear decrease or halt in adherence in the 20 days immediately preceding COVID-19 diagnosis compared to an earlier period (p < 0.01). CONCLUSION: Patterns of continuous positive airway pressure device use by obstructive sleep apnoea patients collected through telemonitoring can indicate the onset of COVID-19 symptoms. Existing telemonitoring platforms could be immediately used to screen for COVID-19, and for other respiratory infections, in this large at-risk population.

Pitolisant for Residual Excessive Daytime Sleepiness in OSA Patients Adhering to CPAP: A Randomized Trial.

BACKGROUND: Excessive daytime sleepiness (EDS) in individuals with OSA syndrome persisting despite good adherence to CPAP is a disabling condition. Pitolisant is a selective histamine H3-receptor antagonist with wake-promoting effects. RESEARCH QUESTION: Is pitolisant effective and safe for reducing daytime sleepiness in individuals with moderate to severe OSA adhering to CPAP treatment but experiencing residual EDS? STUDY DESIGN AND METHODS: In a multicenter, double-blind, randomized (3:1), placebo-controlled, parallel-design trial, pitolisant was titrated individually at up to 20 mg/day and taken over 12 weeks. The primary end point was change in the Epworth Sleepiness Scale (ESS) score in the intention-to-treat population. Key secondary end points were maintenance of wakefulness assessed by the Oxford Sleep Resistance Test, Clinical Global Impressions scale of severity, the patient's global opinion, EuroQoL quality-of-life questionnaire score, Pichot fatigue questionnaire score, and safety. RESULTS: Two hundred forty-four OSA participants (82.8% men; mean age, 53.1 years; mean Apnea Hypopnea Index with CPAP, 4.2/h; baseline ESS score, 14.7) were randomized to pitolisant (n = 183) or placebo (n = 61). ESS significantly decreased with pitolisant compared with placebo (-2.6; 95% CI, -3.9 to -1.4; P < .001), and the rate of responders to therapy (ESS ≤ 10 or change in ESS ≥ 3) was significantly higher with pitolisant (71.0% vs 54.1%; P = .013). Adverse event occurrence (mainly headache and insomnia) was higher in the pitolisant group compared with the placebo group (47.0% and 32.8%, respectively; P = .03). No cardiovascular or other significant safety concerns were reported. INTERPRETATION: Pitolisant used as adjunct to CPAP therapy for OSA with residual sleepiness despite good CPAP adherence significantly reduced subjective and objective sleepiness and improved participant-reported outcomes and physician-reported disease severity. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01071876; URL: www.clinicaltrials.gov; EudraCT N°: 2009-017248-14; URL: eudract.ema.europa.eu.

Impact of a Multimodal Telemonitoring Intervention on CPAP Adherence in Symptomatic OSA and Low Cardiovascular Risk: A Randomized Controlled Trial.

BACKGROUND: One of the major challenges in treating OSA is to achieve adequate CPAP adherence. Telemonitoring has the potential to provide individualized management and early recognition of problems during treatment. RESEARCH QUESTION: What is the effect of a multimodal telemonitoring intervention on treatment adherence, quality of life, and functional status in symptomatic patients with OSA and low cardiovascular risk? STUDY DESIGN AND METHODS: In a multicenter, randomized controlled trial, patients newly diagnosed with OSA were randomly assigned to multimodal telemonitoring for 6 months vs usual care (UC). Telemonitoring consisted of built-in electronic alert algorithms for early adjustment of CPAP treatment in case of side effects, leaks, or persistent residual events. The primary outcome was CPAP adherence (in hours per night). Secondary outcomes included daily symptoms such as fatigue and sleepiness, and quality of life measured by using self-reported questionnaires. RESULTS: A total of 206 patients with OSA and a median age of 50.6 years (interquartile range [IQR], 42.1; 58.1 years) were included in the study; they were predominantly male (63%) with a median BMI of 30.6 kg/m2 (IQR, 26.8; 35.1 kg/m2) and a median apnea-hypopnea index of 45.2 events/h (IQR, 34.0; 60.0 events/h). Of these, 102 received UC and 104 received telemonitoring. After 6 months of treatment, CPAP adherence was similar in the two groups when assessed either by mean duration of usage (4.73 ± 2.48 h per night in the telemonitoring group and 5.08 ± 2.44 h per night in the UC group; P = .30) or in percentage of patients adherent to treatment (> 4 h usage per night, > 70% nights; 64% in the telemonitoring group vs 72% in the UC group; P = .24). There was no significant difference between the groups in effect size of improvement in fatigue and sleepiness. INTERPRETATION: In patients with severe OSA and low cardiovascular risk, multimodal telemonitoring did not increase CPAP adherence. For both the telemonitoring and UC groups, similar improvements in daytime symptoms were achieved. TRIAL REGISTRY: ClinicalTrials.gov; No.: 01796769; URL: www.clinicaltrials.gov.

Biomarkers in patients with heart failure and central sleep apnoea: findings from the SERVE-HF trial.

AIMS: The Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnoea by Adaptive Servo Ventilation in Patients with Heart Failure trial investigated the effects of adaptive servo-ventilation (ASV) (vs. control) on outcomes of 1325 patients with heart failure and reduced ejection fraction (HFrEF) and central sleep apnoea (CSA). The primary outcome (a composite of all-cause death or unplanned HF hospitalization) did not differ between the two groups. However, all-cause and cardiovascular (CV) mortality were higher in the ASV group. Circulating biomarkers may help in better ascertain patients' risk, and this is the first study applying a large set of circulating biomarkers in patients with both HFrEF and CSA. METHODS AND RESULTS: Circulating protein-biomarkers (n = 276) ontologically involved in CV pathways, were studied in 749 (57% of the trial population) patients (biomarker substudy), to investigate their association with the study outcomes (primary outcome, CV death and all-cause death). The mean age was 69 ± 10 years, and > 90% were male. The groups (ASV vs. control and biomarker substudy vs. no biomarker) were well balanced. The "best" clinical prognostic model included male sex, systolic blood pressure < 120 mmHg, diabetes, loop diuretic, cardiac device, 6-min walking test distance, and N-terminal pro BNP as the strongest prognosticators. On top of the "best" clinical prognostic model, the biomarkers that significantly improved both the discrimination (c-index) and the net reclassification index (NRI) of the model were soluble suppression of tumorigenicity 2 for the primary outcome; neurogenic locus notch homolog protein 3 (Notch-3) for CV-death and all-cause death; and growth differentiation factor 15 (GDF-15) for all-cause death only. CONCLUSIONS: We studied 276 circulating biomarkers in patients with HFrEF and central sleep apnoea; of these biomarkers, three added significant prognostic information on top of the best clinical model: soluble suppression of tumorigenicity 2 (primary outcome), Notch-3 (CV and all-cause death), and GDF-15 (all-cause death).

Pitolisant for Daytime Sleepiness in Patients with Obstructive Sleep Apnea Who Refuse Continuous Positive Airway Pressure Treatment. A Randomized Trial.

Rationale: Excessive daytime sleepiness is a common disabling symptom in obstructive sleep apnea syndrome.Objectives: To evaluate the efficacy and safety of pitolisant, a selective histamine H3 receptor antagonist with wake-promoting effects, for the treatment of daytime sleepiness in patients with moderate to severe obstructive sleep apnea refusing continuous positive airway pressure treatment.Methods: In an international, multicenter, double-blind, randomized (3:1), placebo-controlled, parallel-design trial, pitolisant was individually titrated at up to 20 mg/d over 12 weeks. The primary endpoint was the change in the Epworth Sleepiness Scale score. Key secondary endpoints were maintenance of wakefulness assessed on the basis of the Oxford Sleep Resistance test, safety, Clinical Global Impression of severity, patient's global opinion, EuroQol quality-of-life questionnaire, and Pichot fatigue questionnaire.Measurements and Main Results: A total of 268 patients with obstructive sleep apnea (75% male; mean age, 52 yr; apnea-hypopnea index, 49/h; baseline sleepiness score, 15.7) were randomized (200 to pitolisant and 68 to placebo) and analyzed on an intention-to-treat basis. The Epworth Sleepiness Scale score was reduced more with pitolisant than with placebo (-2.8; 95% confidence interval, -4.0 to -1.5; P < 0.001). Wake maintenance tests were not improved. The Pichot fatigue score was reduced with pitolisant. The overall impact of pitolisant was confirmed by both physicians' and patients' questionnaires. Adverse event incidence, mainly headache, insomnia, nausea, and vertigo, was similar in the pitolisant and placebo groups (29.5% and 25.4%, respectively), with no cardiovascular or other significant safety concerns.Conclusions: Pitolisant significantly reduced self-reported daytime sleepiness and fatigue and improved patient-reported outcomes and physician disease severity assessment in sleepy patients with obstructive sleep apnea refusing or nonadherent to continuous positive airway pressure.Clinical trial registered with www.clinicaltrials.gov (NCT01072968) and EU Clinical Trials Register (EudraCT 2009-017251-94).